Snow on mountains
In the Natural Colour RGB images the snow covered area appears cyan or bright blue because its reflectivity is high both in the 0.87 and in the 0.63 micron channels, while much lower in the 1.6 micron channel. The 1.6 micron radiation is strongly absorbed by snow and ice crystals. The image below shows the snow covered Alps on 14 March 2014 at 08:52 UTC. Some peaks and ridges in the Apennines are also covered by snow.
The following image shows the snow covered Pyrenees and Massif Central on 08 March 2014 at 10:06 UTC.
Explanation of the cyan colour of snow on mountains in the Natural Colour RGB (see the recipe):
With a strong contribution of the green and the blue colour beam over snow, the resulting colour is cyan.